Pathways leading to early growth faltering: an investigation into the importance of mucosal damage and immunostimulation in different socio-economic groups in Nepal

Abstract

Early childhood growth retardation persists in developing countries despite decades of nutritional interventions. Adequate food is necessary, but not sufficient, to ensure normal growth where there is ubiquitous exposure to infection. Pathways associated with infection, small intestinal mucosal damage and chronic immunostimulation remain largely undemonstrated in countries other than The Gambia. We conducted a longitudinal study of one squatter and one middle-class group (n 86, 3 -18 month olds) to assess these relationships in Nepal. Growth, mucosal damage index (MDI; urinary lactose:creatinine ratio adjusted for body weight), morbidity reports, and blood concentrations of albumin, a-1-acid glycoprotein, IgG and Hb, were recorded monthly. Growth status worsened dramatically from 6 to 18 months, with squatters more stunted (height-for-age Z-score (HAZ), P, 0·001) and underweight (weight-for-age Z-score (WAZ), P¼ 0·009) than middle class. IgG increased with age, was elevated in squatter children, and negatively related to WAZ (P¼ 0·034). MDI showed significant negative associations with growth performance, explaining 9 and 19 % of height and weight deficits (DHAZ, P¼0·004; DWAZ, P,0·001). Unexpectedly, these associations were weaker in squatter children, namely in the group which showed poorer growth, elevated morbidity, greater pathogen exposure (IgG) and higher MDI (P, 0·001). In Nepal, as in The Gambia, children exhibit poor growth, mucosal damage and immunostimulation. The relative impact of pathways associated with infection and undernutrition may, however, differ across socio-economic groups: in poorer children, the impact of mucosal damage and immunostimulation could be masked by nutritional constraints. This has important implications for public health interventions.Infant growth: Intestinal permeability: Malnutrition: Immune response: Nepal: The Gambia: Public health policy Despite decades of nutritional and health interventions, childhood growth faltering remains a feature of the life course in most developing countries (1) : worldwide, 25 % of children under 5 years are under-weight, 31 % are stunted and 11 % are wasted (2) . It is during the first 2 years of life, when growth is rapid, that children seem particularly vulnerable to environmental constraints; the World Bank (3) recently identified this period as 'the window of opportunity for addressing undernutrition'. Fig. 1 specifies the two key mechanisms that cause growth faltering. Much attention has been paid to undernutrition (pathway A), yet nutritional intervention programmes have invariably produced disappointing results, failing to raise growth performance to expected levels (4,5) . It is increasingly recognised that although an adequate supply of nutrients is clearly required, this is not sufficient to ensure normal childhood growth. Frequent and persistent infections (pathway B) resulting, for example, from increased pathogen exposure due to poor hygiene, also restrict growth (6 -8) . Undernutrition and infection are closely inter-relat...

Geophagy is Associated with Environmental Enteropathy and Stunting in Children in Rural Bangladesh

“…[2][3][4][5][6][7][8][9][10] Furthermore, these findings provide further validation of the use of the EE score as composite marker of EE in children. The lack of a significant association between geophagy and alpha-1-antitrypsin, myeloperoxidase, and neopterin is likely a reflection of our small sample size and the EE score representing a more comprehensive measure of intestinal inflammation.…”

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Fecal Markers of Environmental Enteropathy are Associated with Animal Exposure and Caregiver Hygiene in Bangladesh

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